I did what Boomer recommends a few years ago and ended up with a Sharp. It's not silent but it is fine even for me -- and I am super-sensitive to noise. Also nice is a feature that turns the AC off when the desired temperature has been reached and then turns it on again when needed.

Question:
Does anyone know of a room fan that looks nice? I loved the suggestion of the Lakso fan above, but I don't like the way it looks and it MUST be parked right in the focal area of my living room.

on a friend's recommendation, i bought a Panasonic that i've been happy with, i think it is 10,000 btus, most quiet a/c i've ever had

I just went thru this whole process and did my homework on which is the best unit, less noise, good energy rating etc.
My suggestion is to a buy a Fedder. They have been making AC units for years (solely AC units), you can buy them at Home Depot, they are not as noisy as say a Sears model, and they are way better rated than a Danby.

I have a 10,000 btu sharp and it is super quiet and absolutely freezing in my space (awesome!) but then again i'm about 125 sq ft less than you. However, it should easily be sufficient for 40 sq ft.

As with most things, you get what you pay for. Any of those low budget made in ChHina brands at HD, Lowes, Pc Richard etc (GE, Westinghouse, GoldStar, Frigidaire) are noisy as hell, especially as the units get larger. IMO, Friedrich is the only way to go for ay A/C 10,000 BTUs or higher.

I think our is called a Friedrich Quietmaster or something--I know "quiet" is in the name and it is MUCH quieter than the GE we had. Also way more expensive.